/** ****************************************************************************** * @file stm32g4xx_hal_crc_ex.c * @author MCD Application Team * @brief Extended CRC HAL module driver. * This file provides firmware functions to manage the extended * functionalities of the CRC peripheral. * ****************************************************************************** * @attention * * Copyright (c) 2019 STMicroelectronics. * All rights reserved. * * This software is licensed under terms that can be found in the LICENSE file * in the root directory of this software component. * If no LICENSE file comes with this software, it is provided AS-IS. * ****************************************************************************** @verbatim ================================================================================ ##### How to use this driver ##### ================================================================================ [..] (+) Set user-defined generating polynomial through HAL_CRCEx_Polynomial_Set() (+) Configure Input or Output data inversion @endverbatim ****************************************************************************** */ /* Includes ------------------------------------------------------------------*/ #include "stm32g4xx_hal.h" /** @addtogroup STM32G4xx_HAL_Driver * @{ */ /** @defgroup CRCEx CRCEx * @brief CRC Extended HAL module driver * @{ */ #ifdef HAL_CRC_MODULE_ENABLED /* Private typedef -----------------------------------------------------------*/ /* Private define ------------------------------------------------------------*/ /* Private macro -------------------------------------------------------------*/ /* Private variables ---------------------------------------------------------*/ /* Private function prototypes -----------------------------------------------*/ /* Exported functions --------------------------------------------------------*/ /** @defgroup CRCEx_Exported_Functions CRC Extended Exported Functions * @{ */ /** @defgroup CRCEx_Exported_Functions_Group1 Extended Initialization/de-initialization functions * @brief Extended Initialization and Configuration functions. * @verbatim =============================================================================== ##### Extended configuration functions ##### =============================================================================== [..] This section provides functions allowing to: (+) Configure the generating polynomial (+) Configure the input data inversion (+) Configure the output data inversion @endverbatim * @{ */ /** * @brief Initialize the CRC polynomial if different from default one. * @param hcrc CRC handle * @param Pol CRC generating polynomial (7, 8, 16 or 32-bit long). * This parameter is written in normal representation, e.g. * @arg for a polynomial of degree 7, X^7 + X^6 + X^5 + X^2 + 1 is written 0x65 * @arg for a polynomial of degree 16, X^16 + X^12 + X^5 + 1 is written 0x1021 * @param PolyLength CRC polynomial length. * This parameter can be one of the following values: * @arg @ref CRC_POLYLENGTH_7B 7-bit long CRC (generating polynomial of degree 7) * @arg @ref CRC_POLYLENGTH_8B 8-bit long CRC (generating polynomial of degree 8) * @arg @ref CRC_POLYLENGTH_16B 16-bit long CRC (generating polynomial of degree 16) * @arg @ref CRC_POLYLENGTH_32B 32-bit long CRC (generating polynomial of degree 32) * @retval HAL status */ HAL_StatusTypeDef HAL_CRCEx_Polynomial_Set(CRC_HandleTypeDef *hcrc, uint32_t Pol, uint32_t PolyLength) { HAL_StatusTypeDef status = HAL_OK; uint32_t msb = 31U; /* polynomial degree is 32 at most, so msb is initialized to max value */ /* Check the parameters */ assert_param(IS_CRC_POL_LENGTH(PolyLength)); /* check polynomial definition vs polynomial size: * polynomial length must be aligned with polynomial * definition. HAL_ERROR is reported if Pol degree is * larger than that indicated by PolyLength. * Look for MSB position: msb will contain the degree of * the second to the largest polynomial member. E.g., for * X^7 + X^6 + X^5 + X^2 + 1, msb = 6. */ while ((msb-- > 0U) && ((Pol & ((uint32_t)(0x1U) << (msb & 0x1FU))) == 0U)) { } switch (PolyLength) { case CRC_POLYLENGTH_7B: if (msb >= HAL_CRC_LENGTH_7B) { status = HAL_ERROR; } break; case CRC_POLYLENGTH_8B: if (msb >= HAL_CRC_LENGTH_8B) { status = HAL_ERROR; } break; case CRC_POLYLENGTH_16B: if (msb >= HAL_CRC_LENGTH_16B) { status = HAL_ERROR; } break; case CRC_POLYLENGTH_32B: /* no polynomial definition vs. polynomial length issue possible */ break; default: status = HAL_ERROR; break; } if (status == HAL_OK) { /* set generating polynomial */ WRITE_REG(hcrc->Instance->POL, Pol); /* set generating polynomial size */ MODIFY_REG(hcrc->Instance->CR, CRC_CR_POLYSIZE, PolyLength); } /* Return function status */ return status; } /** * @brief Set the Reverse Input data mode. * @param hcrc CRC handle * @param InputReverseMode Input Data inversion mode. * This parameter can be one of the following values: * @arg @ref CRC_INPUTDATA_INVERSION_NONE no change in bit order (default value) * @arg @ref CRC_INPUTDATA_INVERSION_BYTE Byte-wise bit reversal * @arg @ref CRC_INPUTDATA_INVERSION_HALFWORD HalfWord-wise bit reversal * @arg @ref CRC_INPUTDATA_INVERSION_WORD Word-wise bit reversal * @retval HAL status */ HAL_StatusTypeDef HAL_CRCEx_Input_Data_Reverse(CRC_HandleTypeDef *hcrc, uint32_t InputReverseMode) { /* Check the parameters */ assert_param(IS_CRC_INPUTDATA_INVERSION_MODE(InputReverseMode)); /* Change CRC peripheral state */ hcrc->State = HAL_CRC_STATE_BUSY; /* set input data inversion mode */ MODIFY_REG(hcrc->Instance->CR, CRC_CR_REV_IN, InputReverseMode); /* Change CRC peripheral state */ hcrc->State = HAL_CRC_STATE_READY; /* Return function status */ return HAL_OK; } /** * @brief Set the Reverse Output data mode. * @param hcrc CRC handle * @param OutputReverseMode Output Data inversion mode. * This parameter can be one of the following values: * @arg @ref CRC_OUTPUTDATA_INVERSION_DISABLE no CRC inversion (default value) * @arg @ref CRC_OUTPUTDATA_INVERSION_ENABLE bit-level inversion (e.g. for a 8-bit CRC: 0xB5 becomes 0xAD) * @retval HAL status */ HAL_StatusTypeDef HAL_CRCEx_Output_Data_Reverse(CRC_HandleTypeDef *hcrc, uint32_t OutputReverseMode) { /* Check the parameters */ assert_param(IS_CRC_OUTPUTDATA_INVERSION_MODE(OutputReverseMode)); /* Change CRC peripheral state */ hcrc->State = HAL_CRC_STATE_BUSY; /* set output data inversion mode */ MODIFY_REG(hcrc->Instance->CR, CRC_CR_REV_OUT, OutputReverseMode); /* Change CRC peripheral state */ hcrc->State = HAL_CRC_STATE_READY; /* Return function status */ return HAL_OK; } /** * @} */ /** * @} */ #endif /* HAL_CRC_MODULE_ENABLED */ /** * @} */ /** * @} */